The present invention relates to an apparatus for feeding both cut-sheet and fan fold sheet paper within a printer, and in particular to preventing the slack formed in paper fed in a printer.
A conventional paper feeding apparatus as shown in FIG. 1 includes a print head 106. A push tractor 101 feeds fan fold paper 102 downstream in the direction of arrow G to print head 106. A pair of feed rollers 103 are positioned on the downstream side of print head 106. Cut sheet paper is fed by feed rollers positioned upstream of print head 106 in conjunction with feed rollers 103.
The conventional paper feeding apparatus has been satisfactory. However, there is a large space between push tractor 101 and feed rollers 103 to allow for feeding a cut sheet to print head 106. Therefor, when fan fold sheet 102 is fed by push tractor 101, as fan fold paper 102 travels in the direction of arrow G toward feed rollers 103 slack is likely to occur in the paper. This results from the fact that the paper travels such a large distance unsupported. This slack does not become removed until fan fold paper 102 has been fed for several lines to as many as ten lines after the leading edge of fan fold paper 102 has reached feed rollers 103. Because the paper feed rate fluctuates due to the slack, the printing dot produced on the paper by print head 106 cannot be located accurately on fan fold paper 102 during this slack and slack recovery period. As a result, high precision printing cannot be guaranteed.
Accordingly, it is desired to provide a paper feeding apparatus which overcomes the disadvantages of the prior art device described above by providing an intermediate paper feeding structure to eliminate slack during the feeding of fan fold paper.